Lennox CHA16, Руководство по обслуживанию

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POWER EXHAUST
FAN PERFORMANCE
Air
Volume
(cfm)
4200
3800
3500
3200
2700
2200
Return Air System
Static Pressure
(inches Water Gauge)
0
.05
.10
.15
.20
.25
Exhausted)
TABLE 16
Page 42
2-EMDH16M Horizontal Economizer
(823, 953, 1353, 1603 only)
A separate horizontal economizer is available for 12.5 ton
and smaller units which require the use of an economizer
in combination with horizontal air discharge. Although the
EMDH16M is physically different than the REMD16M (fig
ure 40) both economizers are wired the same and are
identical in terms of function.
FIGURE 40
AVAILABLE FOR
12.5TON AND SMALLER
UNITS ONLY
OPTIONAL GED16
GRAVITY EXHAUST DAMPER
EMDH16M HORIZONTAL ECONOMIZER
FIGURE 41
TYPICAL EMDH16M SHOWN INSTALLED
Unit
EMDH16M
3-Economizer Accessories
a-GED16 Gravity Exhaust Dampers
(economizers not equipped with PED16)
Optional GED16 gravity exhaust dampers may be
connected to REMD16M or EMDH16M economiz
ers. Automatic exhaust dampers provide positive
pressure relief in return air duct. See fiigure 40.
b-PED16 Power Exhaust Damper
(1853, 2553, 2753, 3003 only)
Optional PED16
power exhaust
fans (figure 42) are
used in conjunction
with REMD16M
economizer to pro
vide forced ex
haust of return
air.PED16 consists
of two fans (figure
42) which install in
the return air por
tion of the econo
mizer and a control kit which installs in the unit filter
section.
The PED16 is operated by a relay control kit (figure
43) located in the unit filter access section.A mercury
switch located on the damper blades senses econo
mizer operation.As the damper blades open the mer
cury switch (figure 46) closes and energizes a relay in
the control kit.When the relay is energized a set of
normally open contacts close and the PED16 ex
haust fans are energized.
PED16 fan motors use unit line voltage except in
575V units.575V units use 460V fan motors.A 575V
to 460V transformer and fuse are provided in the
PED16 control kit to provide stepped-down voltage to
the fan motors.
The PED16 control kit (figure 43) and the economizer
enthalpy control (figure 51) are designed to be located
in the same area of the unit filter section simultaneous
ly.The enthalpy control is attached to a standoff
bracket which allows the PED16 control kit to be
installed behind as shown in figure 44.
FIGURE 42
PED16 POWER EXHAUST DAMPER
J18
P18
PED16
REMD16M
REMD16M
PED16
CONTROL KIT